80 is nothing and -4% ROI is a breakeven streak not a losing streak as someone already pointed out. I remember Raptor writing about a 1000 breakeven streak, course he plays a bajillion tables at once so that was probably only a couple of days, still 80 is nothing. That's right, NOTHING.

You say you've had bad luck, if that's the case you have nothing to worry about so don't fret. If it helps you can always try splitting your play between 33s and 55s.

There may be an adjustment period from playing with 800 chips to 1000 chips.

Hope this helps.